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SETFLDSTATE( ) Function

Assigns a field modification or deletion state value to a field or record in a table or cursor.

SETFLDSTATE(cFieldName | nFieldNumber, nFieldState [, cTableAlias
   | nWorkArea])

Return Value

Logical

Parameters

  • cFieldName| nFieldNumber
    Specifies the name or the number of the field for which the modification or deletion status is assigned. The field number nFieldNumber corresponds to the position of the field in the table or cursor structure. DISPLAY STRUCTURE or FIELD( ) can be used to determine a field's number.

    To set the deletion status for the record, include 0 as the field number.

  • nFieldState
    Specifies a value for the field modification or deletion status. The following table lists the field modification or deletion state value and the corresponding modification or deletion status:

    nFieldState

    Modification or deletion status

    1

    Field has not been modified or deletion status has not changed.

    2

    Field has been modified or deletion status has changed.

    3

    Field in an appended record has not been modified or deletion status has not changed for the appended record.

    4

    Field in an appended record has been modified or deletion status has changed for the appended record.

  • cTableAlias
    Specifies the alias of the table or cursor in which the modification or deletion status is assigned.

  • nWorkArea
    Specifies the work area of the table or cursor in which the modification or deletion status is assigned. The field modification or deletion state value is assigned for the table or cursor open in the currently selected work area if SETFLDSTATE( ) is issued without the optional cTableAlias or nWorkArea arguments.

Remarks

Visual FoxPro uses field state values to determine which fields in tables or cursors are updated. SETFLDSTATE( ) makes it possible for you to control which fields Visual FoxPro attempts to update, regardless of which fields have been modified in the table or cursor.

Example

The following example demonstrates how you can use SETFLDSTATE( ) to change the field status. MULTILOCKS is set to ON, a requirement for table buffering. The customer table in the testdata database is opened, and CURSORSETPROP( ) is then used to set the buffering mode to optimistic table buffering (5).

GETFLDSTATE( ) is issued to display a value (1) corresponding to the unmodified state of the cust_id field before it is modified. The cust_id field is modified with REPLACE, and GETFLDSTATE( ) is issued again to display a value (2) corresponding to the modified state of the cust_id field.

SETFLDSTATE( ) is used to change the field status of the cust_id field back to 1 (unmodified). GETFLDSTATE( ) is issued again and displays 1, corresponding to the state of the cust_id field assigned by SETFLDSTATE( ). TABLEREVERT( ) is used to return the table to its original state.

CLOSE DATABASES
SET MULTILOCKS ON  && Must be on for table buffering
SET PATH TO (HOME(2) + 'Data\')     && Sets path to database
OPEN DATABASE testdata  && Open testdata database
USE Customer     && Open customer table
= CURSORSETPROP('Buffering', 5, 'customer')  && Enable table buffering

CLEAR
? GETFLDSTATE('cust_id')  && Displays 1, not modified
REPLACE cust_id    WITH '***'  && Changes field contents
? GETFLDSTATE('cust_id')  && Returns 2, field modified
= SETFLDSTATE('cust_id', 1)  && Change the field status
? GETFLDSTATE('cust_id')  && Displays 1, not modified
= TABLEREVERT(.T.)  && Discard all table changes

See Also

Reference

DELETED( ) Function

DISPLAY STRUCTURE Command

FIELD( ) Function

GETFLDSTATE( ) Function

Other Resources

Functions

Language Reference (Visual FoxPro)